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Test D: No Module/Network Communications - Unable To Communicate With Any Module

  1. Turn ignition off. Inspect NGS tester connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  2. Inspect Data Link Connector (DLC) C252 for physical damage, bent terminals or corrosion. C252 is located below driver's side of instrument panel, to left of steering column above fuse junction panel. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  3. Disconnect TCM connector is located behind instrument cluster. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, measure resistance of Yellow/Red wire between terminal No. 6 at TCM connector C277B and terminal No. 1 at Data Link Connector (DLC) C252. See Figure and Figure . If resistance is 5 ohms or more, repair open Yellow/Red wire. If resistance is less than 5 ohms, go to next step.
  4. Measure resistance of Yellow/Black wire between terminal No. 7 at TCM connector C277B and terminal No. 2 at DLC C252. If resistance is 5 ohms or more, repair open Yellow/Black wire. If resistance is less than 5 ohms, go to next step.
  5. Connect New Generation Star (NGS) tester to Data Link Connector (DLC) C252, if not already connected. Turn ignition on. Run DIAGNOSTIC TEST MODE RESULTS for Powertrain Control Module (PCM). If the results are:
    • LINK COMMUNICATION ERROR
    • MODULE NOT RESPONDING
    • CHECK IGNITION STATUS
    • CHECK CABLE (DDL ADAPTER) CONNECTIONS
    Go to next step. If results are not as listed, replace TCM. Retest system.
  6. Turn ignition off. Disconnect ABS module connector C249, located behind center of dash. Turn ignition on. Run DIAGNOSTIC TEST MODE RESULTS for PCM. If the results are:
    • LINK COMMUNICATION ERROR
    • MODULE NOT RESPONDING
    • CHECK IGNITION STATUS
    • CHECK CABLE (DDL ADAPTER) CONNECTIONS
    Go to next step. If results are not as listed, replace ABS module. Retest system.
  7. Turn ignition off. Deactivate air bag system. See AIR BAG RESTRAINT SYSTEMS - VILLAGER article. Disconnect air bag diagnostic monitor. Air bag diagnostic monitor is located in bottom of center console. Turn ignition on. Run DIAGNOSTIC TEST MODE RESULTS for PCM. If the results are:
    • LINK COMMUNICATION ERROR
    • MODULE NOT RESPONDING
    • CHECK IGNITION STATUS
    • CHECK CABLE (DDL ADAPTER) CONNECTIONS
    Go to next step. If results are not as listed, replace ABS air bag diagnostic monitor. Retest system.
  8. Turn ignition off. Disconnect PCM connector. PCM is located behind glove box. Turn ignition on. Measure voltage between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If any voltage is present, go to step  24. If no voltage is present, go to next step.
  9. Measure voltage between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If any voltage is present, go to step  20. If no voltage is present, go to next step.
  10. Turn ignition off. Measure resistance between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, go to step  16.
  11. Measure resistance between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If resistance is more than 10 k/ohms, see SELF-DIAGNOSTICS - VILLAGER article in ENGINE PERFORMANCE. If resistance is 10 k/ohms or less, go to next step.
  12. Disconnect in-line 84-pin connector C170. In-line connector C170 is located behind left side of dash above fuse junction panel. Measure resistance between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Black wire between in-line connector C170 and ABS module. ABS module behind center of dash. If resistance is 10 k/ohms or less, go to next step.
  13. Disconnect in-line 16-pin connector C255. In-line connector C255 is located behind instrument cluster. Measure resistance between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Black wire between in-line connector C255 and TCM. TCM is located behind instrument cluster. If resistance is 10 k/ohms or less, go to next step.
  14. Disconnect in-line 12-pin connector C2021. In-line connector C2021 is located behind center top of dash. Measure resistance between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Black wire between in-line connector C2021 and air bag diagnostic monitor. Air bag diagnostic monitor is located in bottom of center console. If resistance is 10 k/ohms or less, go to next step.
  15. Disconnect in-line 6-pin connector C272. In-line connector C272 is located behind center top of dash. Measure resistance between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Black wire between in-line connector C272 and PCM. PCM is located behind glove box. If resistance is 10 k/ohms or less, repair short to ground in Yellow/Black wire between in-line connector C272, in-line connector C2021, in-line connector C255, in-line connector C170 and DLC C252.
  16. Disconnect in-line 84-pin connector C170. In-line connector C170 is located behind left side of dash above fuse junction panel. Measure resistance between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Red wire between in-line connector C170 and ABS module. ABS module behind center of dash. If resistance is 10 k/ohms or less, go to next step.
  17. Disconnect in-line 16-pin connector C255. In-line connector C255 is located behind instrument cluster. Measure resistance between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Red wire between in-line connector C255 and TCM. TCM is located behind instrument cluster. If resistance is 10 k/ohms or less, go to next step.
  18. Disconnect in-line 12-pin connector C2021. In-line connector C2021 is located behind center top of dash. Measure resistance between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Red wire between in-line connector C2021 and air bag diagnostic monitor. Air bag diagnostic monitor is located in bottom of center console. If resistance is 10 k/ohms or less, go to next step.
  19. Disconnect in-line 6-pin connector C272. In-line connector C272 is located behind center top of dash. Measure resistance between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If resistance is more than 10 k/ohms, repair short to ground in Yellow/Red wire between in-line connector C272 and PCM. PCM is located behind glove box. If resistance is 10 k/ohms or less, repair short to ground in Yellow/Red wire between in-line connector C272, in-line connector C2021, in-line connector C255, in-line connector C170 and DLC C252.
  20. Disconnect in-line 84-pin connector C170. In-line connector C170 is located behind left side of dash above fuse junction panel. Measure voltage between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If voltage is zero volts, repair short to voltage in Yellow/Black wire between in-line connector C170 and ABS module. ABS module behind center of dash. If voltage is present, go to next step.
  21. Disconnect in-line 16-pin connector C255. In-line connector C255 is located behind instrument cluster. Measure voltage between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If voltage is zero volts, repair short to voltage in Yellow/Black between in-line connector C255 and TCM. TCM is located behind instrument cluster. If voltage is present, go to next step.
  22. Disconnect in-line 12-pin connector C2021. In-line connector C2021 is located behind center top of dash. Measure voltage between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If voltage is zero volts, repair short to voltage in Yellow/Black between in-line connector C2021 and air bag diagnostic monitor. Air bag diagnostic monitor is located in bottom of center console. If voltage is present, go to next step.
  23. Disconnect in-line 6-pin connector C272. In-line connector C272 is located behind center top of dash. Measure voltage between ground and DLC C252 terminal No. 2 (Yellow/Black wire). If voltage is zero volts, repair short to voltage in Yellow/Black between in-line connector C272 and PCM. PCM is located behind glove box. If voltage is present, repair short to voltage in Yellow/Black between in-line connector C272, in-line connector C2021, in-line connector C255, in-line connector C170 and DLC C252.
  24. Disconnect in-line 84-pin connector C170. In-line connector C170 is located behind left side of dash above fuse junction panel. Measure voltage between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If voltage is zero volts, repair short to voltage in Yellow/Red wire between in-line connector C170 and ABS module. ABS module behind center of dash. If voltage is present, go to next step.
  25. Disconnect in-line 16-pin connector C255. In-line connector C255 is located behind instrument cluster. Measure voltage between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If voltage is zero volts, repair short to voltage in Yellow/Red wire between in-line connector C255 and TCM. TCM is located behind instrument cluster. If voltage is present, go to next step.
  26. Disconnect in-line 12-pin connector C2021. In-line connector C2021 is located behind center top of dash. Measure voltage between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If voltage is zero volts, repair short to voltage in Yellow/Red wire between in-line connector C2021 and air bag diagnostic monitor. Air bag diagnostic monitor is located in bottom of center console. If voltage is present, go to next step.
  27. Disconnect in-line 6-pin connector C272. In-line connector C272 is located behind center top of dash. Measure voltage between ground and DLC C252 terminal No. 1 (Yellow/Red wire). If voltage is zero volts, repair short to voltage in Yellow/Red wire between in-line connector C272, in-line connector C2021, in-line connector C255, in-line connector C170 and DLC C252.
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